I found Reliability an issue, with respect to maintaining connections over any length of time considerably improved with official module, whereas in-tree driver dropped connections frequently at least on my test hardware.
See attached recent release notes for Official driver, particularly the x86_64 fix (afaik is not included with in-tree version).
If the Official drivers support the intended hardware they can easily be recompiled if requested to support various power saving modes, which are currently not enabled by default and AFAIK not available at all with in tree module.